Effectiveness of COVID-19 vaccines against variants of concern, Canada

@inproceedings{Nasreen2021EffectivenessOC,
  title={Effectiveness of COVID-19 vaccines against variants of concern, Canada},
  author={Sharifa Nasreen and Hannah Chung and Siyi He and Kevin Antoine Brown and Jonathan B. Gubbay and Sarah A. Buchan and Deshayne B. Fell and Peter C. Austin and Kevin L. Schwartz and Maria E. Sundaram and Andrew J. Calzavara and Branson Chen and Mina Tadrous and Kumanan Wilson and Sarah E. Wilson and Jeffrey C. Kwong},
  booktitle={medRxiv},
  year={2021}
}
Objectives: To estimate the effectiveness of BNT162b2 (Pfizer-BioNTech), mRNA-1273 (Moderna), and ChAdOx1 (AstraZeneca) vaccines against symptomatic SARS-CoV-2 infection and severe outcomes (COVID-19 hospitalization or death) caused by the Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), and Delta (B.1.617.2) variants of concern (VOCs) during December 2020 to May 2021. Methods: We conducted a test-negative design study using linked population-wide vaccination, laboratory testing, and health… 

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